H
E
E
L
E
M
E
N
T
S
CG is equal to GQ, and QR to RP,
AG is also equal to MQ, and QL to RF, [I.36]
But
MQ is equal to QL, for they are complements of the parallelogram ML; [I.43] therefore
AG is also equal to RF;
therefore
the four areas AG, MQ, QL, RF are equal to one another.
Therefore
the four are quadruple of AG.
